upgrader: add Upgrader.DesiredVersion

state/api/upgrader/upgrader_test.go

 // Copyright 2012, 2013 Canonical Ltd.
 // Licensed under the AGPLv3, see LICENCE file for details.
 
 package upgrader_test
 
 import (
         stdtesting "testing"
 
         gc "launchpad.net/gocheck"
 
@@ skipping 124 matching lines @@
         err = statetesting.SetAgentVersion(s.BackingState, vers)
         c.Assert(err, gc.IsNil)
         wc.AssertNoChange()
         vers = version.MustParse("10.20.35")
         err = statetesting.SetAgentVersion(s.BackingState, vers)
         c.Assert(err, gc.IsNil)
         wc.AssertOneChange()
         statetesting.AssertStop(c, w)
         wc.AssertClosed()
 }
+
+func (s *upgraderSuite) TestDesiredVersion(c *gc.C) {
+        cur := version.Current
+        curTools := &tools.Tools{Version: cur, URL: ""}
+        curTools.Version.Minor++
+        s.rawMachine.SetAgentTools(curTools)
+        // Upgrader.DesiredVersion returns the *desired* set of tools, not the
+        // currently running set. We want to be upgraded to cur.Version
+        stateVersion, err := s.st.DesiredVersion(s.rawMachine.Tag())
+        c.Assert(err, gc.IsNil)
+        c.Assert(stateVersion, gc.Equals, cur.Number)
+}